Study of the jointed rock mass uniaxial compression strength anisotropy and scale effect

The method of prediction of strength and deformation characteristics of jointed rock mass using numerical finite-element modeling is considered. The sequence of creation of numerical geomechanical model of rock mass is considered, the rock mass is modeled explicitly by the scheme of existing discontinuities in the considered conditions of apatite-nepheline ores deposit, the schemes of conducting virtual tests are offered. The purpose of study of rock mass model behavior is to determine stress distribution dependences in jointed rock mass, to determine model parameters for quantitative estimation of influence of spatial orientation of discontinuities systems on ultimate strength of rock sample. A methodology is described for conducting a series of numerical experiments over a jointed rock mass of various dimensions, where the rock mass environment is specified discretely taking into account the contact mechanical characteristics between rock blocks. The characteristics of the decrease in the strength of a rock mass with an increase in its size were obtained based on the results of virtual tests — with an increase in the area of a jointed rock mass there is the decrease in the values of its mechanical characteristics until the formation of a representative elementary volume.

Verbilo P. E., Vilner M. A. Study of the jointed rock mass uniaxial compression strength anisotropy and scale effect. MIAB. Mining Inf. Anal. Bull. 2022;(6−2):47—59. [In Russ]. DOI: 10.25018/0236_1493_2022_62_0_47.

Verbilo P. E., Cand. Sci. (Eng.), assistant professor, https://orcid.org/0000-0001-6776-5866, Russia, St. Petersburg Mining University, 199106, St. Petersburg, 21-ya V. O., 2, e-mail: verbilo_pe@pers.spmi.ru;
Vilner M.A., postgraduate student, https://orcid.org/ 0000-0002-0424-100X, Russia, St. Petersburg Mining University, 199106, St. Petersburg, line 21 V. O., 2, e-mail: mary.vilner@gmail.com.

Verbilo Pavel Eduardovich, e-mail: verbilo_pe@pers.spmi.ru.

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